Lowered alpha value of one tile windows and rwindows

Because of personal dislike towards the blue tint, I lowered the alpha value in the middle of the full tile windows so they look more like what the directional windows were like.

![windows_alpha](https://cloud.githubusercontent.com/assets/5390315/5336382/39736934-7ec4-11e4-814d-39ca5995236e.png)

Only changed window and rwindow, not tinted or shuttle windows.

Poll on forums: https://tgstation13.org/phpBB/viewtopic.php?f=10&t=2196